Exactly 10 years ago, Palestinian gunmen barricaded themselves inside the Church of the Nativity in Bethlehem and waged a five-week battle with the surrounding Israeli tanks and soldiers. Now, the site widely held to be the birthplace of Jesus has become the center of a new political battle, this one pitting Palestinians against the guardians of the church, among others.

At issue is the Palestinian effort to have the ancient Basilica declared a World Heritage site by the U.N.’s cultural agency, Unesco, into which “Palestine” was voted as a full member state last October. The World Heritage designation might sound harmless enough, given that it spans more than 900 culturally significant sites ranging from the Grand Canyon to Moscow’s Red Square, and that its purpose is to preserve unique natural and man-made treasures. And the resultant cachet often boosts local economies by attracting tourists, although veneration of the Church of Nativity in Christianity already does that. “There is intense government interest in the [designation] process every year,” says a Western diplomat at Unesco. “This is a big deal.”

But the “big deal” in this instance is Bethlehem’s location at the heart of one of the Middle East’s most intractable conflicts. Israel has opposed designating the Church of the Nativity a World Heritage site. Already annoyed by Unesco’s implied recognition of Palestinian statehood, it believes that the Palestinians are using the bid as yet another symbolic step to bolster their cause amid the paralysis of the Middle East peace process.

On top of those objections come the doubts from religious leaders. In an April letter to President Mahmoud Abbas, the heads of the three denominations that have for centuries jointly cared for the ancient structure — the Greek Orthodox and Armenian Patriarchs, and the head of the Franciscan Church, which represents the Vatican in Jerusalem — declined to support Abbas’s effort. In the letter, a copy of which was shown to TIME this week, they wrote, “We do not think it opportune to deal with this request.”

The religious leaders do not spell out the full reasons for their opposition, but cite among their “minor” considerations the fact that “the operating conditions required by the statutes of Unesco, necessary to include it, do not exist.” That seems to refer to the Palestinians’ request that Unesco’s World Heritage committee treat the Bethlehem church as an “emergency” site, allowing them to jump the normal 18-month waiting period for consideration. Abbas wants the request to be considered next week, when the committee meets in St. Petersburg, Russia; the vote is expected on Monday. World Heritage emergency rulings are rare, usually taken when armed conflicts threaten the very survival of a particular site, for example the remains of the ancient Bamiyan Bhuddas in Afghanistan, which the Taliban blew up shortly before the Afghan War began. The Palestinians argued that the Church of the Nativity’s maintenance and restoration was suffering from the Israeli occupation of the West Bank. (Israel controls Bethlehem’s access points, while Palestinian police patrol inside of the city.) Perhaps as a sign of the delicate balancing act facing Church leaders along the fault-lines of the Israeli-Palestinian conflict, the religious leaders ended their letter to Abbas by saying, “We are confident, Mr. President, that we can still count on your understanding and once again thank you for your friendship and support.”

The bid to designate the Church as a World Heritage site may have less to do with Abbas’s “friendship and support” for its faith communities, than with Palestinian national goals. It marks the Palestinians’ first initiative as a Unesco member, and is clearly a test of their clout within the Paris-based body. Palestine, which doesn’t yet exist as a sovereign nation state, was nonetheless named as a full member-state of Unesco by a simple 107-14 vote among its membership, which (unlike the U.N. Security Council) does not give any country veto powers. In response, the U.S. Congress quickly blocked $80 million in U.S. funding to Unesco — about one-quarter of the organization’s budget.

Still, it’s far from clear that the Palestinians will win their push for World Heritage status of the church, as well as for the Old City of Bethlehem; their application is among 34 sites under consideration in St. Petersburg. Typically, the committee goes along with the recommendations of Unesco’s experts, who examine each site in advance, and present their findings. The Palestinians argued that among the threats to the Church of the Nativity is the incessant hordes of tourists who cram into the space every day of the year, in a chaotic jumble of tours. In their 11-page report, the experts agreed, saying that there is “the need for better management of visitors, as the exceptionally high number of people within the Church of the Nativity at any one time is impacting adversely on its conservation of the fabric.”

Yet, the experts also saw no reason for the Palestinians to skip the usual waiting process for World Heritage status, saying, “The nomination should be resubmitted for the normal assessment process.” That would require the Palestinians to submit a new application next February — for a vote in mid-2014.